What does the offset 20 signify in the below code?

using ModelingToolkit

@variables x y z

@parameters a b c

----Define a nonlinear system

eqs = [0 ~ - y - (z+20),

0 ~ x + a * y,

0 ~ b + (z+20) * (x - c)]

ns = NonlinearSystem(eqs, [x,y,z], [a,b,c])

nlsys_func = generate_function(ns)[2] # second is the inplace version

rossler = ModelingToolkit.eval(nlsys_func)

du = zeros(3); u = ones(3)

params = (0.2,0.2,5.7)

j_func2 = generate_jacobian(ns)[2] # second is in-place

j2! = ModelingToolkit.eval(j_func2)

using NLsolve

nlsolve((out, x) → rossler(out, x, params), (out, x) → j2!(out, x, params), ones(3))

out:

Results of Nonlinear Solver Algorithm

- Algorithm: Trust-region with dogleg and autoscaling
- Starting Point: [1.0, 1.0, 1.0]
- Zero: [0.007026204834100122, -0.035131024170500603, -19.9648689758295]
- Inf-norm of residuals: 0.000000
- Iterations: 8
- Convergence: true
- |x - x’| < 0.0e+00: false
- |f(x)| < 1.0e-08: true

- Function Calls (f): 9
- Jacobian Calls (df/dx): 9